N-(dialkylphosphonoalkyl)-carbamic acid alkyl esters

ABSTRACT

Certain alkyl esters of N-(dialkylphosphonoalkyl)-carbamic acid, their use as flameproofing agents for textiles and a process for their production.

United St:

Petersen et al.

N-( DIALKYLPHOSPHONOALKYL)- CARBAMIC ACID ALKYL ESTERS Inventors: HarroPetersen, Frankenthal;

Friedrich Fuchs, Kirchheim; Peter Scharwaechter, Ludwigshafen, all ofGermany BASF Aktiengesellschatt, Ludwigshafen (Rhine), Germany Filed:June 17, 1974 Appl. No.: 479,893

Assignee:

Foreign Application Priority Data June 19. 1973 Germany ..233/l02 US. Cl260/932; 106/15 FP; 117/136; 260/937; 260/938; 260/970 Int. Cl. C07f9/40 Primary Exam'irlerAnton H. Sutto Assistant ExaminerRichard L.Raymond Attorney, Agent, or Firm-Johnston, Keil, Thompson & Shurtleff [57 ABSTRACT Certain alkyl esters of N-(dialkylphosphonoalkyl)- carba'micacid, their use as flameproofing agents for textiles and a process fortheir production.

16 Claims, N0 Drawings N-( DIALKYLPHOSPHONOALKYL )-CARBAM1C ACID ALKYLESTERS The invention relates to certain alkyl esters of N-(dialkylphosphonoalkyl)-carbamic acids, to their use as flameproofingagents for textiles and also to a method of manufacturing them.

It is known that combustible fibrous material, particularly such ascontains or consists of cellulose, can be treated with organicsubstances containing phosphorus to make them flameproof.Tetrahydroxymethylphosphonium chloride (THPC) used in common withaminoplastics and trisaziridinylphosphine oxide (APO) have becomeparticularly well known for this purpose. Both have seriousdisadvantages. THPC tends to be an odor nuisance, and APO is difficultto handle because of its toxicity.

N-monomethylol and N-dimethylol compounds of dialkyl esters ofcarbamoylalkanephosphoric acids are known from Belgian Pat. Nos. 647,376and 713,511. They are recommended therein as flameproofing agents forcellulose. It has been found however that finishes obtained therewithexhibit inadequate resistance to treatments with chlorine. A process forthe washresistant flameproofing of cellulosic fibrous material isdescribed in German Laid-Open Specification (DOS) No. 1,930,308according to which the monomethylol or dimethylol compounds ofdialkoxyphosphonomonoalkyl carbamates are used as nitrogeneousphosphorus compounds.

These have the disadvantage that they cause stiffening and yellowing.

There are only a very limited number of prior art textile flamep'roofingagents which are useful in practice; the present invention therefore hasas an object the provision of novel outstanding flameproofing agents fortextiles.

The invention comprises a flameproofing agent for textiles in which adialkylphosphonoalkyl ester group is attached to the nitrogen atom of acarbamic acid ester, a process for the production of the same and theuse of the same. The substances according to the invention have thegeneral formula:

in which R, R R and R are alkyl of one to'five carbon atoms, R and R mayalso be halogenated and particularly chlorinated alkyl or together maybe alkylcne of two to three carbon atoms, R may also-be hydrogen,methylol or alkoxymethyl of one to three carbon atoms in the alkoxy, Ais linear or branched alkylene of two to eight carbon atoms of which atleast two are situated in the chain linking nitrogen and phosphorus andR may also be a radical of the formula:

O R2 O u l H in which X is linear or branched alkylene of two to eightcarbon atoms which may be interrupted by oxygen atoms and R R and R havethe above meanings.

Particular industrial significance attaches to those substances of theformula (1) in which R, R and R are unsubstituted alkyl preferably ofone or two carbon atoms, R is hydrogen, methylol or alkoxymethyl of oneto three carbon atoms and particularly one carbon atom in the alkoxy, Ais linear alkylene of three or four and particularly of three carbonatoms and X is alkylene of two to four carbon atoms which may contain anether group.

Preferred examples of substances of the formula (1) are:

3 a 4 Other suitable examples of substances of the formula in which R R,R, R, D and n have the same mean- (I) are: ings as in formulae (V) and(VI) and R, R, R, E and according to theiprocessof the invention byreacting a thereof) have the same meaning as R R R D and n,

dialkyl ester of phosphorus acid of the formula (IV): and the totalnumber of carbon atoms in E, R", R and i R like that of D, R R and R is'no more than 6, in the presence of an organic peroxide as catalyst, by

7, O i heatin the mixture to the decom osition tern erature ll g p p Wof 'the peroxide, 1f desired' methlolatmg the product 5 (1V) formed withformaldehyde and if desired acetalizing the methylol groups thusintroduced with an alkanol of one to three carbon atoms.

In this process it has proved to be suitable to use the dialkyl ester ofphosphorous acid (formula (IV)) in exwith an olefinically unsaturatedcarbamic acid ester of the formula (V) or (VI):

Q F fi fi cess, for example in from 1.5 to 5 times the molar i R R" R Vamount based on the starting material (V). Secondary reactions aresuppressed and the yields are improved in or n this way. 7 7

'7 r 7 Examples of suitable starting compounds of the for-(RP-fi'=fi-(Dj,,l7lfi-O+g-X mula (V) are substances of the followingstructures:

R:- vl f. O c H ,(()(()l ll(CHM(H=(H, V L

I V (,-,H,. in which R to R have the meanings given in formula (I), Xhas the meanings given in formulae (II) and (III) H;(;,()(()N-(=('H: andR R and R are hydrogen or alkyl of one or two 40 H N a 2 fm carbonatoms, D is an alkylene of one to three carbon 7 atoms and i1 zero or I,and the sum of the carbon H,,( -,()(()-NH-(H=-(H atoms of D, R, R and Ris a maximum of 6, or the formula (VII): 7 7

V H,,(. .-ot orl\ H=( H-t,-,H. u m 0 R2 5 R1 CHH R j=(E),,,-O- -IJ-(D),,-( =-R (VII) Examples of suitable substances of formula (VI) are:

II II o 0 (H2 Examples of suitable substances of formula (Vll) are:

o 0H, (3H.

Any organic peroxide may be used as the catalyst. Examples areditertiary-butyl peroxide and dibenzoyl peroxide.

The catalyst is conveniently used in an amount of from O. l to, percentbased on the weight of the reaction mixture.

The starting materials (IV) and (V), (VI) or (VII) are generally reactedby simple mixing, adding the catalyst and heating the mixture. Thereaction temperature depends on the type of peroxide and may easily beascertained by preliminary experiment. As a rule it is within the rangefrom 90 to 180C. The reaction is usually over in thirty to ninetyminutes. The reaction may be carried out in the presence of an inertsolvent. The products obtained may if desired by reacted by aconventional method in an alkaline medium with formaldehyde to form thecorresponding methylol compounds. These may then be acetalized by aconventional method in the presence of an acid catalyst with an alkanolof one to three carbon atoms. The optional steps of methylolation andacetalization may for example be carried out as follows:

For methylolation the substance obtained by reaction ofthe components(IV) and (V), (VI) or (VII) is mixed with formaldehyde in a molar ratiocorresponding to the desired degree of methylolation. A basic substance,for example an alkali metal hydroxide, is added to the mixture until thepH is from 8 to 11 and preferably from 9 to 10. After the exothermicreaction is over the methylol compound formed is neutralized.

For acetalization it has proved to be suitable to dissolve the methylolcompound in the alkanol provided for the acetalization, to add to thesolution a catalytic amount of an .acid and preferably of a strong acid,to heat the mixture until the acetalization'reaction is over and then toneutralize the product. The excess alkanol may then be removed bydistillation.

The substance of formula (I) may be used with very good results as aflameproofing agent for textile material and particularly for textilematerial which contains or consists of natural or regenerated cellulose.It has proved to be advantageous to .add an aminoplastforming substanceto the finishing liquor to achive a finish which is durable tolaundering. Suitable aminoplast-forming substances include all methyloland al koxymethyl compounds of acyclic and cyclic ureas, for example ofurea, thiourea, ethylenurea, propylenurca, glyoxalmonoureine,triazinones and urones, of monocarbamic acid dicarbamic esters,cyanamide and dicyanamide and also aminotn'azines and preferably themethylol and methoxymethyl compounds of melamine. In the case ofcompounds of formula (I) in which I Hi;

the radical R is a methylol or alkoxymethyl group a reaction with thehydroxyl groups of the cellulose is achieved in known manner but in thiscase also a combination with an aminoplast-forming substance givesimproved durability to washing.

The textile material to be treated is impregnated with a dispersion orsolution of one or more substances of formula (I) with or without one ormore aminoplastforming substances and then reaction is carried out inthe presence of at least one acid and/or potentially acid catalyst. Itis preferred to use the substance of formula (I) and if desired theaminoplast-forming substances in the form of aqueous impregnationliquors. The concentration of substance of formula (I) in the liquor isgenerally from 250 to 600 g/liter. The amount of any aminoplast-formingsubstance which it is necessary to add is generally from to 260 g/liter.

The amount of flameproofing agent (I) applied to the fiber should befrom 25 to percent and preferably from 28 to 50 percent. Theflameproofing effect is thus retained even after the loss of some of thefinish in numerous washings. The critical limits below which theflameproofing effect is substantially lost are at about 20 percent offlameproofing agent based on the weight of fiber (in the case ofcellulosic fibers). The amount of aminoplast-forming substance appliedto the fiber may be from O to 25 percent and preferably from 10 to 20percent by weight.

It is preferred to use a padding mangle for the impregnation. Theimpregnated material is freed from excess impregnating liquor in knownmanner by sequeezing. The impregnated fibrous material may be dried andthen heated in the presence of an acid or potentially acid catalyst at atemperature of up to 200C and preferably at from to C. The reaction isgenerally over in from one minute to six minutes under these conditions.

Acid or potentially acid catalysts for finishing with N-alkoxymethylcompounds are known and commonly used. Examples are inorganic or organicacids such as sulfuric acid, hydrochloric acid, phosphoric acid, boricacid and oxalic acid and salts which have an acid reaction or which formacids during use for example by the action of heat and/or hydrolysis,for example ammonium and amine salts, magnesium chloride, zinc chlorideand zinc nitrate. Particularly good flameproofing effects are achievedwhen monoammonium or diammonium phosphate is used. The reaction of thesubstances of formula (I) and if desired of the aminoplast formingsubstances with the textile material is carried out, as already stated,in the presence of these catalysts. This may be effected by applying thecatalysts, preferably in the form of aqueous solutions, to the materialto be finished before or after the impregnation of the same. It ispreferable however to introduce the catalyst direct into theimpregnating liquor containing the substance of formula (1).Concentrations of catalyst of from 1 to 40 g/liter have generally provedto be suitable.

It is also possible to use together with the substances of formula (I)and with any aminoplast-forming substances other finishing agents, forexample nitrogenfree hydroxymethyl or alkoxymethyl compounds,polyethylene glycol formals and compounds containing epoxy groups, asfor example glycol diglycidol ethers. It is also possible to useconventional water-repellent, softening, levelling, wetting or otherfinishing agents. Examples of water-repellent agents are the knownparaffin wax emulsions containing aluminum or zirconium and alsosilicon-containing preparations and perfluorated aliphatic compounds.Examples of softeners are oxyethylation products of higher fatty acids,fatty alcohols and fatty acid amides, high molecular weight polyglycolethers and their esters, higher fatty acids, fatty alcohol sulfonates,stearyl-N,N-ethylenurea and stearylamidomethylpyridinium chloride.Examples of levelling agents are watersoluble salts of acid esters ofpolybasic acids with ethylene oxide or propylene oxide adducts oflong-chain oxyalkylatable base materials. Examples of wetting agents aresalts of alkylnaphthalenesulfonic acids, the alkali metal salts ofsulfonated dioctyl succinate and the adducts of alkylene oxides to fattyalcohols, alkylphenol, fatty amines and the like. Other finishing agentsinclude for example cellulose ethers or esters and alginates, and alsosolutions or dispersions of synthetic polymers, for example of po1yethylene, polyamides, oxyethylated polyamides, polyvinyl esters, polyvinylalcohols, polyacrylic acid or esters or amides thereof and thecorresponding polymethacrylic compounds, polyvinyl propionate,polyvinylpyrrolidone, copolymers, for example those of acrylic ormethacrylic esters and at least percent by weight of acrylic and/ormethacrylic acid, of vinyl chloride and acrylic esters, of butadiene andstyrene or acrylonitrile or of a-dichloroethylene, B-chloroalkylacrylicesters or vinyl-B-ethyl ether and acrylamide or the amides of crotonicor maleic acid or of N-methylolmethacrylamide and other polymerizablecompounds.

After the reaction with the substances of formula l) and if desired withaminoplast-forming substances the textile material has an excellentflameproofing sub stances the textile material has an excellentflameproofing which is very resistant to hydrolysis and washing. Thetreated material may be washing, rinsed and dried by conventionalmethods.

The following Examples illustrate the invention. The parts andpercentages specified are by weight. Parts by weight bear the samerelationship to parts by volume as the kilogram to the liter.

EXAMPLE 1 A mixture consisting of 115 parts of methyl N allylcarbamatcand 110 parts of dimethyl phosphite and 10 parts of ditertiarybutylperoxide are dripped within 1 hour into 1 10 parts of dimethyl phosphiteat 150 to 160C. After the exothermic reaction is over the whole isstirred for half an hour at 165C, excess dimethyl phosphite is removedin vacuo and 214 parts percent of theory) ofa clear viscous oil (methylN- (3-dimethylphosphonopropyl )-carbamate) is obtained. C H NO O (225)C71- 1 1% N71. I P% calculated: 37.2 7.1 6.2 13.8

found: 36.5 7.5 6.3 14.2

EXAMPLE 2 A mixture of 225 parts of methylN-(3-dimethylphosphonopropyl)-carbamate and 75 parts of 40 percentformaldehyde solution is brought to pH 9.0 with 5N caustic sodasolution. The temperature rises to 50C; the whole is stirred for 1 hourat from 45 to 55C. 331 parts ofa clear viscous oil is obtained having acontent of free formaldehyde of 3.2 percent and of combined formaldehydeof 6.6 percent. The degree of methylolation is 61 percent.

EXAMPLE 3 A mixture consisting of parts of methyl N- allylcarbamate and138 parts of diethyl phosphite and also 10 parts of ditertiarybutylperoxide are dripped within 1 hour into 138 parts of diethyl phosphiteat C. The product is worke up as in Example 1. 248 parts (94 percent oftheory) of a clear viscous oil (methylN-(3-diethylphosphonopropyl)-carbamate) is obtained.

A mixture consisting of 129 parts of ethyl N- allylcarbamate and 110parts of dimethyl phosphite and also 10 parts of ditertiarybutylperoxide are dripped during 1 hour into 1 10 parts of dimethyl phosphiteat 150 to 160C. The reaction mixture is worked up as described inExample 1. 230 parts (96 percent of theory) of a clear and viscous oil(ethyl N-( 3- dimethylphosphonopropyl )-carbamate) is obtained.

C H NO P (239) C7! H7! N7e P7( calculated: 40.1 7.5 5 .9 13.0 found:40.0 7.8 5.5 13.2

EXAMPLE 5 c.11 0 A mixture of 129 parts of ethyl N-allylcarbamate. 138parts of diethyl phosphite and parts of diterti- EXAMPLE 7 I 01.0 cu,

CH2OH A mixture of 239 parts of methyl N-(3-dimethylphosphono-Z-methylpropyl )-carbamate and 75 parts of percentaqueous formaldehyde solution is adjusted to pH 9.0 with 5N caustic sodasolution. The temperature rises to C. The whole is stirred at thistemperature for 1 hour. 344 parts of a clear viscous oil is obtainedhaving a content of free formaldehydeof 4.3 percent and of combinedformaldehyde of 5.2 percent. The degree of methylolation is 59.5percent.

EXAMPLE 8 ary-butyl peroxide is dripped within 1 hour into 138 parts ofdiethyl phosphite at 160C. The reaction mixture is worked up asdescribed in Example 1. 253 parts (95 percent of theory) of a clear andviscous oil (ethyl OCH A mixture consisting of 272 parts of diethyleneglycol N,N'-diallylbiscarbamate, 220 parts of dimethyl phosphite and 25parts by volume of ditertiary-butyl peroxide are dripped into 220 partsof dimethylphosphite at 165C within 1 hour. The whole is stirred foranother fifteen minutes at 165C. The reaction mixture is worked up asdescribed in Example 1. 480 parts (96 percent of theory) of a clearviscous oil is obtained (diethylene glycol N,N '-di-( 3-dimethylphosphonopropyl )-biscarbamate C16H34N2OHP2 calculated:

6.9 5.7 12. found: 5 3

EXAMPLE 9 129 parts of methyl methallylcarbamate and 10 parts ofditertiary-butyl peroxide is dripped within 1 hour at 160C into 220parts of dimethyl phosphite. After the exothermic reaction is over thewhole is stirred for another half an hour at 165C, excess dimethylphosphite is removed in vacuo and 234 parts (94 percent of theory) of aclear viscous oil is obtained (methyl N-(3-dimethyl-phosphono-Z-methylpropyl )-carbamate C H NO P (239) C7( H71 N?P% calculated: 40.1 7.5 5.8 13.0 found: 39.7 7.7 5.5 12.3

l OCH A mixture of 492 parts of diethylene glycol N,N'-di-(3-dimethylphosphonopropyl )-biscarbamate (the compound from Example 8)and parts of 40 percent aqueous formaldehyde solution is adjusted to pH9 with 5N caustic soda solution.

The temperature rises to 50C and the whole is stirred for one hour atthis temperature.

732 parts of a clear viscous oil is obtained having a content of freeformaldehyde of 4.0 percent and of combined formaldehyde of 5.1 percent.The degree of methylolation is 62 percent.

EXAMPLE 10 CH O OCH concentrated in vacuo. 342 parts (95 percent ofthe-- ory) of a clear viscous oil (3-dimethylphosphonopropyl ester ofN-(3-dimethyl'phosphonopropyl)-carbamic acid) is obtained.

calculated: found:

EXAMPLE l 1 A mixture of 361 parts of the S-dimethylphosphonopropylester of N-(3-dimethylphosphonopropyl)- carbamic acid from Example 10and 825 parts of 40 percent aqueous formaldehyde solution is adjusted topH 9 with N caustic soda solution and brought to reaction for two hoursat 50C. The whole is then cooled, dissolved in 500 parts of methanol,adjusted to pH 3 to 4 with hydrochloric acid and heated for thirtyminutes under reflux. After cooling, the whole is neutralized with 5Ncaustic soda solution and concentrated in vacuo.

431 parts of a clear viscous oil is obtained having a total formaldehydecontent of 5.8 percent and a phosphorus content of 14.9 percent(calculated: 15.3 per cent).

I cn on 150 parts of hexamethylolmelamine pcntamethyl ether and 20 partsof monoammonium phosphate to a wet pickup of 100 percent, dried at 100Cand condensed for five minutes at 170C. The cloth is washed at 70C fortwo minutes with 5 parts of soda per liter of water to remove unreactedmaterial. After having been rinsed with hot water at 70C the cloth isdried.

(mon

12 The cotton twill thus finished is given the vertical flame testaccording to DIN 53,906. It exhibits a flameproofing effect whichremains intact after fifty washings at 95C. In the following Tables, thefollowing abbreviations are used:

UC untreated cloth AA after application 10W (30W, W) after having beenwashed at C with 1.5 g/liter of a commercial detergent 10 (30, 50) timesBT burned through Treated cloth UC AA 10W 30W 50W test time in seconds 66 6 6 6 burning time in seconds 21 0 0 0 glow time in seconds 65 0 0 (Jtear length in mm ET )5 1 l0 1 10 load in grams 50 50 50 50 EXAMPLE 1 3Cotton twill having a weight of about 176 g per square meter is finishedby the method of application described in Example 12 with an aqueousliquor con taining per liter 400 parts of the compound from Exam ple 7:

cn o CH cn on 200 parts of hexamethylolmelamine pentamethyl ether and 20parts of monoammonium phosphate.

The cotton twill finished in this way is given the vertical flame testaccording to DIN 53,906. It shows a good flame-proofing effect which isretained even after the cloth has been washed 50 times at 95C:

Treated cloth Cotton twill having a weight of about 176 g per squaremeter is finished by the method of application described in Example 12with an aqueous liquor containing per liter 500 parts of the compoundfrom Example 9:

parts of hexamethylolmelamine pentamethyl ether and 20 parts of 45percent aqueous phosphoric acid.

The cotton twill finished in this way is treated in the vertical flametest according to DIN 53,906. It shows a good flameproofing effect whichis intact after fifty washings at 95C.

Treated cloth UC AA 10W 30W 50W test time (seconds) 6 6 6 6 6 burningtime (seconds) 21 0 glow time (seconds) 65 0 0 tear length (mm) ET 100100 l()() 90 load (g) 50 50 t) 50 EXAMPLE 15 Cotton twill weighing about176 g per square meter is finished by the method of Example in anaqueous liquor which contains per liter 285 parts of the compound fromExample 1 l:

CH;,O zi

l parts of hexamethylolmelamine pentamethyl ether and parts ofmonoammonium phosphate.

The cloth finished in this way exhibits a good flameproofing effect inthe vertical flame test according to DIN 53,906 and this is intact after50 washings at the boil.

1. A substance of the formula:

R2 OR4 in which R, R, R and R are identical or different and are alkylof one to five carbon atoms,

R and R may also be chlorinated alkyl of one to five carbon atoms ortogether may be alkylene of two to three carbon atoms,

R may also be hydrogen, methylol or alkoxymethyl of one to three carbonatoms in the alkoxy,

A is unbranched or branched alkylene of two to eight carbon atoms ofwhich at least two are situated in the chain connecting nitrogen andphosphorus, and

R may also be a radical of the formula:

X is linear or branched alkylene of two to eight carbon atoms which maybe interrupted by oxygen atoms, and R R and R have the meanings givenabove.

2. A substance as set forth in claim 1 wherein R, R and R areunsubstituted alkyl of l or 2 carbon atoms, R is hydrogen, methylol oralkoxymethyl'of l to 3 carbon atoms, Ais linear alkylene of 3 or 5carbon atoms and X is alkylene of 2 to 4 carbon atoms or alkylene of 2to 4 carbon atoms containing 1 ether group.

3. A substance as set forth in claim 1 having the formula:

4. A substance as set forth in claim 1 having the formula:

5. A substance as set forth in claim 1 having the formula:

6. A substance as set forth in claim 1 having the for mula:

7. A substance as set forth in claim 1 having the formula:

9. A substance as set forth in claim 1 having the formula:

10. A substance as set forth in claim 1 having the formula:

11. A substance as set forth in claim 1 having the formula:

CHQOH 12. A substance as set forth in claim 1 having the formula:

13. A substance as set forth in claim 1 having the formula:

14. A substance as set forth in claim 1 having the formula:

15. A substance as set forth in claim 1 having the formula:

16. A substance as set forth in claim 1 having the formula:

1. A SUBSTANCE OF THE FORMULA:
 2. A substance as set forth in claim 1wherein R1, R3 and R4 are unsubstituted alkyl of 1 or 2 carbon atoms, R2is hydrogen, methylol or alkoxymethyl of 1 to 3 carbon atoms, A islinear alkylene of 3 or 5 carbon atoms and X is alkylene of 2 to 4carbon atoms or alkylene of 2 to 4 carbon atoms containing 1 ethergroup.
 3. A substance as set forth in claim 1 having the formula:
 4. Asubstance as set forth in claim 1 having the formula:
 5. A substance asset forth in claim 1 having the formula:
 6. A substance as set forth inclaim 1 having the formula:
 7. A substance as set forth in claim 1having the formula:
 8. A substance as set forth in claim 1 having theformula:
 9. A substance as set forth in claim 1 having the formula: 10.A substance as set forth in claim 1 having the formula:
 11. A substanceas set forth in claim 1 having the formula:
 12. A substance as set forthin claim 1 having the formula:
 13. A substance as set forth in claim 1having the formula:
 14. A substance as set forth in claim 1 having theformula:
 15. A substance as set forth in claim 1 having the formula: 16.A substance as set forth in claim 1 having the formula: